function Drag(id) {
	var _this = this;
	this.disX = 0;
	this.disY = 0;
	this.oDiv = document.getElementById(id);
	this.oDiv.onmousedown = function(ev) {
		_this.fnDown(ev)
		return false
	}
}
Drag.prototype.fnDown = function(ev) {
	var _this = this;
	var oEvent = ev || event;
	this.disX = oEvent.clientX - this.oDiv.offsetLeft;
	this.disY = oEvent.clientY - this.oDiv.offsetTop;
	document.onmousemove = function(ev) {
		_this.fnMove(ev)
	}
	document.onmouseup = function(ev) {
		_this.fnStop(ev)
	}
}
Drag.prototype.fnMove = function(ev) {
	var oEvent = ev || event;
	this.oDiv.style.left = oEvent.clientX - this.disX + 'px';
	this.oDiv.style.top = oEvent.clientY - this.disY + 'px';
}
Drag.prototype.fnStop = function() {
	document.onmousemove = null;
	document.onmouseup = null;
}
